Refrigerator Having Frozen Food Thawing Function

ABSTRACT

The present invention relates to a refrigerator ( 1 ) comprising a fresh food compartment ( 2 ) wherein objects to be cooled are placed and at least one thawing compartment ( 4 ) disposed inside the fresh food compartment ( 2 ), wherein the frozen objects are placed and having at least one heating means ( 3 ) providing the interior to be heated.

The present invention relates to a refrigerator having the function of thawing frozen foods.

In refrigerators having freezing and fresh food compartments, when some of the foodstuffs stored in the freezing compartment are desired to be consumed, first the food has to be taken out of the freezing compartment to be thawed and thereafter prepared for consumption. In order to perform the thawing process, the fresh food compartment, with a higher temperature than the freezing compartment, is provided with special cabinets disposed therein, that are equipped with special heating mechanisms and whereat only the thawing process is performed. In the state of the art, realization of the thawing process is actuated by the user in the special cabinet. The user provides the start of the thawing process in the special cabinet by means of a start button.

In the state of the art Japanese Patent Document No. JP6137739, a refrigerator is described having a de-freezing chamber wherein operation is controlled depending on the temperature and weight data of the food placed therein.

In the state of the art Japanese Patent Document No. JP7055319, a refrigerator is described comprising a thawing chamber having a start pushbutton which starts or ends the thawing process.

The aim of the present invention is the realization of a refrigerator that starts the thawing process when the frozen object is placed into the thawing compartment.

The refrigerator realized in order to attain the aim of the present invention, explicated in the first claim and the respective claims thereof, comprises at least one thawing compartment disposed inside the fresh food compartment, having at least one heating means providing the interior to be heated and wherein the frozen objects are placed, at least one first sensor that detects the temperature of the thawing compartment interior when a low temperature object is placed into the thawing compartment and a control unit that calculates a first temperature change rate (dT₁/dt₁) according to the temperature value (T₁) delivered from the first sensor, that compares the calculated first temperature change rate (dT₁/dt₁) with the limit temperature change rate (dT/dt)_(limit) prerecorded in its memory, providing the thawing compartment to be heated and the thawing process to be started by activating the heating means in case the first temperature change rate (dT₁/dt₁) is greater than the limit temperature change rate (dT/dt)_(limit).

In an embodiment of the present invention, the refrigerator comprises a resistance type heating means.

In an embodiment of the present invention, the refrigerator comprises the thawing compartment having a base with high thermal conductivity, the heating means extending along the bottom surface of the base and the first sensor that detects the temperature of the base when a frozen object is placed in the thawing compartment.

In an embodiment of the present invention, the refrigerator comprises at least one fan providing the air therein to be propelled and at least one second sensor that detects the temperature of the thawing compartment interior after the heating means starts to operate and the control unit that operates/stops the heating means and the fan during the thawing process by comparing a lower limit temperature value (T_(lower)) and an upper limit temperature value (T_(upper)) recorded in its memory predetermined by the producer, with the temperature value (T₂) detected by the second sensor.

In an embodiment of the present invention, the control unit calculates a second temperature change rate (dT₂/dt₂) according to the temperature value (T₂) detected by the second sensor and provides the operating/stopping of the heating means and the fan according to the calculated second temperature change rate (dT₂/dt₂).

In an embodiment of the present invention, the control unit ends the operation of the heating means and the fan if the second temperature change rate (dT₂/dt₂) is smaller than the determined limit temperature change rate (dT/dt)_(limit) prerecorded in its memory by the producer.

In an embodiment of the present invention, the refrigerator comprises an insulation element that extends along the lower surface of the heating means.

In an embodiment of the present invention, the first sensor is disposed on the base whereon the frozen object is placed.

In an embodiment of the present invention, the base is produced from metal material.

In an embodiment of the present invention, the refrigerator comprises at least one alerter that informs the user when the thawing process is started.

In an embodiment of the present invention, the refrigerator comprises at least one alerter that informs the user when the thawing process is ended.

By means of the present invention, a refrigerator is realized comprising the control unit having the thawing compartment wherein the thawing process is started automatically when a frozen object is placed therein. Consequently, any kind of intervention by the user is not required for starting the thawing process.

A refrigerator realized in order to attain the aim of the present invention is illustrated in the attached figures, where:

FIG. 1—is the perspective view of a refrigerator.

FIG. 2—is the partial perspective view of the refrigerator having a thawing compartment.

FIG. 3—is the sideways cross-sectional view of a thawing compartment.

The elements illustrated in the figures are numbered as follows:

-   1. Refrigerator -   2. Fresh food compartment -   3. Heating means -   4. Thawing compartment -   5. First sensor -   6. Control unit -   7. Second sensor -   8. Base -   9. Insulation element -   10. Fan -   11. Alerter

The refrigerator (1) comprises a fresh food compartment (2) wherein objects to be cooled are placed and at least one thawing compartment (4) disposed inside the fresh food compartment (2), having at least one heating means (3) providing the interior to be heated and wherein the frozen objects are placed (FIG. 1, FIG. 2).

The refrigerator (1) of the present invention furthermore comprises a first sensor (5) that detects the temperature of the thawing compartment (4) interior when a frozen object is placed into the thawing compartment (4) and a control unit (6) that calculates a first temperature change rate (dT₁/dt₁) according to the temperature value (T₁) detected by the first sensor (5), that compares the calculated first temperature change rate (dT₁/dt₁) with a determined limit temperature change rate (dT/dt)_(limit) prerecorded in its memory by the producer, providing the thawing process to be started and the frozen object to be thawed by activating the heating means (3) if the calculated first temperature change rate (dT₁/dt₁) is greater than the limit temperature change rate (dT/dt)_(limit). The temperature of the thawing compartment (4) is almost equal to the temperature of the fresh food compartment (2) since the thawing compartment (4) is disposed inside the fresh food compartment (2). When the frozen object is placed into the thawing compartment (4), the interior temperature of the thawing compartment (4) changes due to temperature difference between the frozen object and the thawing compartment (4). If the first temperature change rate (dT₁/dt₁) calculated by the control unit (6) is greater than a determined limit temperature change rate (dT/dt)_(limit) prerecorded in its memory by the producer, the heating means (3) is activated by the control unit (6). The thawing process is provided to be started by providing the heating of the interior of the thawing compartment (4). Thus, the process of thawing the object placed into the thawing compartment (4) is started automatically by the control unit (6) without requiring user intervention (FIG. 3).

In an embodiment of the present invention, the refrigerator (1) comprises a resistance type heating means (3). The operation of the heating means (3) is regulated by the control unit (6). The frozen object is provided to be thawed effectively by means of the heating means (3) disposed in the thawing compartment (4).

In an embodiment of the present invention, the refrigerator (1) comprises the thawing compartment (4) having a base (8) produced from a material with high thermal conductivity and the heating means (3) disposed on the bottom surface of the base (8), and the first sensor (5) that detects the temperature of the base (8). The temperature of the base (8) falls when the frozen object is placed on the base (8) due to low temperature of the frozen object. When the frozen object is placed in the thawing compartment (4), the control unit (6) activates the heating means (3) and provides the process of thawing the frozen food to be started by providing the interior of the thawing compartment (4) to be heated, in the case the first temperature change rate (dT₁/dt₁) determined according to the temperature values (T₁) detected by the first sensor (5) within a certain time interval is greater than the limit temperature change rate (dT/dt)_(limit). The first sensor (5) is provided to precisely detect the temperature decrease occurring on the base (8) due to the placing of the frozen object on the base (8) by means of the first sensor (5) being disposed on the base (8) and on the same surface as the frozen object (FIG. 3).

In an embodiment of the present invention, the refrigerator (1) comprises at least one fan (10) providing the air therein to be propelled and at least one second sensor (7) that detects the temperature of the thawing compartment (4) interior during the thawing process and the control unit (6) that controls the operation of the heating means (3) and the fan (10) during the thawing process by comparing a lower limit temperature value (T_(lower)) and an upper limit temperature value (T_(upper)) predetermined by the producer, recorded in its memory with the temperature value (T₂) detected by the second sensor (7). The interior temperature of the thawing compartment (4) that rises by means of the heating means (3) is detected by the second sensor (7). The heating means (3) is stopped by the control unit (6) and the operation of the fan (10) continues when the temperature value (T₂) detected by the second sensor (7) is equal to the upper limit temperature value (T_(upper)). The cold air dispersed from the frozen object in the thawing compartment (4) is provided to be circulated inside the thawing compartment (4) by means of the fan (10) and thus the temperature of the base (8) decreases. When the temperature value (T₂) detected by the second sensor (7) is equal to the lower limit temperature value (T_(lower)), the heating means (3) is started to be operated again by the control unit (6). Thus, the frozen object is provided to be thawed under optimal conditions (FIG. 2).

In an embodiment of the present invention, the control unit (6) calculates a second temperature change rate (dT₂/dt₂) according to the temperature value (T₂) detected by the second sensor (7) and controls the operation of the heating means (3) and the fan (10) according to the calculated second temperature change rate (dT₂/dt₂). If the second temperature change rate (dT₂/dt₂) determined by the control unit (6) is higher than the limit temperature change rate (dT/dt)_(limit) , the fan (10) continues to operate while the heating means (3) is stopped. Thus, the frozen object is provided to be thawed under optimal conditions without being deteriorated.

In an embodiment of the present invention, the control unit (6) ends the operation of the heating means (3) and the fan (10) if the second temperature change rate (dT₂/dt₂) is smaller than the determined limit temperature change rate (dT/dt)_(limit) prerecorded in its memory by the producer. Consequently, the process of thawing the frozen object placed into the thawing compartment (4) is ended by means of the control unit (6) without requiring user intervention.

In an embodiment of the present invention, the refrigerator (1) comprises an insulation element (9) disposed under the heating means (3). Thus, the interior of the fresh food compartment (2) is prevented from heating due to the heat radiated during operation of the heating means (3). Furthermore, energy loss is prevented by preventing the heat radiated from the heating means (3) from leaving the thawing compartment (4) (FIG. 3).

In an embodiment of the present invention, the first sensor (5) is disposed on the upper surface of the base (8). Thus, the first sensor (5) is prevented from being affected by the heat while the heating means (3) operates and the control unit (6) is provided to determine the first temperature change rate (dT₁/dt₁) of the frozen object accurately.

In an embodiment of the present invention, the base (8) is produced from metal material. The heat sensitivity of the metal material is high. Thus, time loss in starting the thawing process is prevented by detecting the temperature of the frozen object.

In an embodiment of the present invention, the refrigerator (1) comprises at least one alerter (11) that enables the user to be informed when the thawing process is started. The user is informed about the start of the thawing process by giving audible or visual signals by means of the alerter (11).

In an embodiment of the present invention, the refrigerator (1) comprises at least one alerter (11) that enables the user to be informed when the thawing process is ended. The operation of the heating means (3) is stopped by the control unit (6) when the thawing process is completed. Meanwhile the user is informed by giving audible or visual signals by means of the alerter (11) (FIG. 1).

By means of the present invention, a refrigerator (1) is realized, having a thawing compartment (4) wherein the first temperature change rate (dT₁/dt₁) in the thawing compartment (4) is detected and the thawing process is started automatically without user intervention when a frozen object is placed into the thawing compartment (4).

It is to be understood that the present invention is not limited to the embodiments disclosed above and a person skilled in the art can easily introduce different embodiments. These different embodiments should also be considered within the scope of the claims of the present invention. 

1. A refrigerator (1) comprising a fresh food compartment (2) wherein objects to be cooled are placed and at least one thawing compartment (4) disposed in the fresh food compartment (2), having at least one heating means (3) providing the interior to be heated and wherein the frozen objects are placed, and characterized by a first sensor (5) that detects the temperature of the thawing compartment (4) interior when a frozen object is placed into the thawing compartment (4) and a control unit (6) that calculates a first temperature change rate (dT₁/dt₁) according to the temperature value (T₁) detected by the first sensor (5), that compares the calculated first temperature change rate (dT₁/dt₁) with a determined limit temperature change rate (dT/dt)_(limit) prerecorded in its memory by the producer, providing the thawing process to be started and providing the frozen object to be thawed by activating the heating means (3) if the calculated first temperature change rate (dT₁/dt₁) is greater than the limit temperature change rate (dT/dt)_(limit).
 2. A refrigerator (1) as in claim 1, characterized by the resistance type heating means (3).
 3. A refrigerator (1) as in claim 2, characterized by the thawing compartment (4) having a base (8) produced from a material with high thermal conductivity and the heating means (3) disposed on the bottom surface of the base (8), and the first sensor (5) that detects the temperature of the base (8).
 4. A refrigerator (1) as in claim 3, characterized by at least one fan (10) providing the air therein to be propelled and at least one second sensor (7) that detects the temperature of the thawing compartment (4) interior during the thawing process and the control unit (6) that controls the operation of the heating means (3) and the fan (10) during the thawing process by comparing a lower limit temperature value (T_(lower)) and an upper limit temperature value (T_(upper)) predetermined by the producer recorded in its memory, with the temperature value (T₂) detected by the second sensor (7).
 5. A refrigerator (1) as in claim 4, characterized by the control unit (6) that calculates a second temperature change rate (dT₂/dt₂) according to the temperature value (T₂) detected by the second sensor (7) and controls the operation of the heating means (3) and the fan (10) according to the calculated second temperature change rate (dT₂/dt₂).
 6. A refrigerator (1) as in claim 5, characterized by the control unit (6) that ends the operation of the heating means (3) and the fan (10) if the second temperature change rate (dT₂/dt₂) is smaller than the determined limit temperature change rate (dT/dt)_(limit) prerecorded in its memory by the producer.
 7. A refrigerator (1) as in claim 6, characterized by an insulation element (9) disposed under the heating means (3).
 8. A refrigerator (1) as in claim 7, characterized by the first sensor (5) disposed on the upper surface of the base (8).
 9. A refrigerator (1) as in claim 8, characterized by the base (8) that is produced from metal material.
 10. A refrigerator (1) as in claim 9, characterized by at least one alerter (11) that enables the user to be informed when the thawing process is started.
 11. A refrigerator (1) as in claim 10, characterized by at least one alerter (11) that enables the user to be informed when the thawing process is ended.
 12. A refrigerator (1) as in claim 1, characterized by the thawing compartment (4) having a base (8) produced from a material with high thermal conductivity and the heating means (3) disposed on the bottom surface of the base (8), and the first sensor (5) that detects the temperature of the base (8).
 13. A refrigerator (1) as in claim 12, characterized by the first sensor (5) disposed on the upper surface of the base (8).
 14. A refrigerator (1) as in claim 12, characterized by the base (8) that is produced from metal material.
 15. A refrigerator (1) as in claim 1, characterized by at least one fan (10) providing the air therein to be propelled and at least one second sensor (7) that detects the temperature of the thawing compartment (4) interior during the thawing process and the control unit (6) that controls the operation of the heating means (3) and the fan (10) during the thawing process by comparing a lower limit temperature value (T_(lower)) and an upper limit temperature value (T_(upper)) predetermined by the producer recorded in its memory, with the temperature value (T₂) detected by the second sensor (7).
 16. A refrigerator (1) as in claim 15, characterized by the control unit (6) that calculates a second temperature change rate (dT₂/dt₂) according to the temperature value (T₂) detected by the second sensor (7) and controls the operation of the heating means (3) and the fan (10) according to the calculated second temperature change rate (dT₂/dt₂).
 17. A refrigerator (1) as in claim 15, characterized by the control unit (6) that ends the operation of the heating means (3) and the fan (10) if the second temperature change rate (dT₂/dt₂) is smaller than the determined limit temperature change rate (dT/dt)_(limit) prerecorded in its memory by the producer.
 18. A refrigerator (1) as in claim 1, characterized by an insulation element (9) disposed under the heating means (3).
 19. A refrigerator (1) as in claim 1, characterized by at least one alerter (11) that enables the user to be informed when the thawing process is started.
 20. A refrigerator (1) as in claim 1, characterized by at least one alerter (11) that enables the user to be informed when the thawing process is ended. 